LIGHT-EMITTING ELEMENT, LIGHT-EMITTING DEVICE, LIGHTING SYSTEM, AND ELECTRONIC DEVICE

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PROBLEM TO BE SOLVED : To provide a light-emitting element which exhibits light emission with high luminance and can be driven at low voltage, and also provide a light-emitting device or an electronic instrument with reduced power consumption. SOLUTION : There is provided a light-emitting element in which n (n is a natural number of two or more) EL layers are provided between an anode and a cathode. In the light-emitting element, between m-th (m is a natural number, 1≤m≤n-1) EL layer and (m+1)-th EL layer, a first layer containing either of an alkali metal, an alkaline earth metal, a rare earth metal, an alkali metal compound, an alkaline earth metal compound, or a rare earth metal compound, a second layer containing a material having a high electron-transporting property in contact with the first layer, and a region containing a material having a high hole-transporting property and an acceptor material in contact with the second layer are provided in this order from the anode side. In addition, there are provided a light-emitting device and an electronic instrument in which the light-emitting element is used. SELECTED DRAWING : Figure 1 COPYRIGHT : (C)2017, JPO&INPIT